Furnace



' Nov. 28, 1944. J, A, NORTON 2,363,742

FURNACE Filed Feb. 10, 1941 2 Sheets-Sheet l I m l3 25 '52 4/ 39' I4- t i I! l T 1!! 1 1' 1H. L 1

INVE/V To)? Lia/717 16. Nor/on; 5y.

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ITTO/YNEY Nov. 28, 1944. J. A. NORTON 3,

FURNACE Filed Feb. 10, 1941 2 Sheets-Sheet 2 INVE/VTGI? ATTORNEY 23 and 24 that are rigid with the furnace walls. This provides an efficient support for the combustion chamber and also provides an expansion joint in the partition between the air chamber l and the space below said air chamber into which the combustion chamber opens.

The flanges 22 are preferably welded to the combustion chamber H3 and extend entirely around the same; The plates 23 and 24 fit tightlyagainst the flanges 22 and form a leak proof joint that is not adversely affected by expansion and contraction and that will not open up and 32 and the flue gas manifold 40 will drain downwardly into the condensate trap 32.

The condensate trap 32 is provided with a drain pipe 32 which may be connected with a sewer allow gases from the compartment below to get into the air compartment Ill.

The upper end of the combustion chamber I5 is closed by a top wall 25. I

A plurality of tubes or smoke conduits 26 .of inverted L shape are connected'with the upper end portion of the combustion chamber l5 Just below the top wall 25. These tubes 26 extend downwardly along the outside of the combustion chamber l5 and communicate at their lower ends with manifold pipes 21.

Preferably two of the manifold pipes 21 extend through a partition wall 28 that separates .compartments I0 and-| and these two pipes are connected by special fittings 29 with short pipes 30 that are welded or otherwise rigidly secured to or may beotherwise used to drain off condensate from the trap 32.

A plurality of baffle plates 43, 4| and 42 are provided in the air compartment between the Y several sections of the pipes 39 to direct the air back and forth in the compartment so that it will be kept in contact with" the pipes 39 for a long period of time.

. ing toward the wall 28 but terminates short of the cap portion 3| of a moisture receptacle or trap 32.

Preferably the trap 32 has a non-corrosive acid proof lining 33 therein. Also sealing members 34 of angle shaped'crosssection are preferably provided between the cap portion 3| and the lining 33. These sealing members are preferably tapered to form a tight seal and are secured by screws 35 to outwardly extending flanges 36 on the trap '32. v

The special fittings 29 form gas tight connections between the pipes 21 and 30 and are secured to said pipes 21 and30 by screws 31 which may be quickly and easily removed or inserted to secure the two furnace units together. An annular rib 38 is provided in each fitting 29 for the ends of the pipes 21 and 30 to abut against and this helps to provide a gas tight joint.

A plurality of runs or units of flue gas tubing 39 are provided in side by Side relation in the air compartment I In Fig. '2, I have shown eight runs or units of this tubing 39 positioned side by side but it will be understood that a greater or less number of these runs or units may be pro- Vided.

Each run or unit of this tubing 39 is made up of a plurality of straight sections inclined relative to the horizontal and positioned one above another and connected at their ends by shorter upright sections.

The lowermost end portion of each run of tubing 39 is connected with the cap member 3| of the condensate trap 32 and the uppermost end portion of each run of tubing 39 is connected with a flue gas manifold 40 that extends crosswise of the furnace housing and is adapted-to be connected with a chimney.

Preferably the runs of tubing 39 are made up of sections of non-corrosive pipe of good heat conductive qualities, such as copper pipe, welded or brazed together.

All portions of the tubing units '39 are inclined relative to the horizontal in such a manner that any condensate which is condensed in said tubing 39 at any location between the condensate trap corners.

A driven fan 45 is provided .in a fan housing 46 in the lowermost portion of the air compartment The fan housing 46 is connected by a passageway 41- with the'lower portion of the air compartment 10. Air from the space surround ing the fan housing enters said fan housing through openings 48 in the end portions of the fan. housing and is discharged through the passageway 41 into the compartment ID. One opening' 48 is shown.

A screen 49 is provided above the fan housing extending from the trap 32 to the outside wan of the furnace and an air filter or air cleaning pad 50 of the usual form is provided on the screen 49. Preferably the screen 49 and air filter 50 extend entirely across the housing so that most of the air which passes downwardly between the right hand end of the bafiie plate 43, Fig. i, and the adjacent furnace wall I2 will come in contact with and pass through the air filter.

A small amount of air will pass through the opening 44 between the wall 28 and the adjacent end of thebafile plate 43 and will pass over the condensate trap on its way to the fan and pick up heat from this portion of the housing and from the condensate trap.

Preferably a door 5| is provided in the housing wall shown at the right'in Fig. 1 to afford access 'toithe compartment containing the fan and the filters and the condensate trap. fAn inlet conduit 53 'for cold air is connected with the upper end portion of the air inlet chamber I and an outlet conduit 54 for heated air is connected with the u er end portion of the air chamber "1.. I

In the operation of the furnace shown in Figs.

'1 and 2'the heated products of combustion move upwardly in the combustion chamber I5, which is relatively long in proportion to its cross. sectiohal area.- By the time these-combustion prod: 'ucts reach the upper end of th chamber l5 coinbustionthereof will be substantially complete; 1 Thehct combustion products will ass down- .wardly through the p'i esze to the manifold pipes 21. Thence these products, whichwill be cooling as they travel, will pass through the cap member 3| and upwardly through the tubes 39 and out through th flue gas manifold 40 to the chimney. v

The direction of movement of the air will, for

the most part, be opposite to the direction of movement of the heated gases, the cold air entering the furnace at the location where the combustion gases are coldest and the heated thereof. heated gases and air it i possible to have the combustion gases leave the furnace at a temperature considerably lower than the temperature at which the-air leaves the furnace;

My arrangement of the combustion chamber a and the heat exchange pipes and conduits keeps the airthat is to be heated in contact with the pipes that carry the combustion products for a long period of time. Also by providing numerous.

pipes of relatively small diameter I obtain a relatively large surface area for the exchange of heat.

to produce a furnace in which substantially all of the useful heat is taken out of the flue gases and these gases leave the furnace at a very low temperature. This results in the condensation of moisture in the flue gas conduits 26, 21 and 39, and especially in the colderconduits 39. This condensed moisturemust be disposed of and the trap 32 provides an efficient and reliable means for taking care'of the-same.

The flue gases discharge from my furnace at furnace the temperature of discharging flue gas is above 300 F. i 1 The trap thus cooperates to makepossible and practical the use of the highly efiici'entheat exchange means provided in this furnace.

It is to be noted that all of the conduits 26, 21 and 39 are positioned so as to drain-into the trap 32. v

Preferablythe conduit area through whichthe combustion products discharge is kept substan tially constant from the point where {the combustion products leave the combustion chamber to the discharge manifold 40.

Obviously changes in my inventionmay be made within the scope and spirit of the following claims. I

I claim:

1. In a furnace, a combustionchamberya. fur-' nace housing surrounding said combustion chamber, a heat exchange chamber; a condensatetrapl in said heat exchange chamber; a cap member of inverted trough shape forming a cover for said condensate trap; flue gas conduits in said I All of the features above described cooperate air leaving the furnace from the hottest portion By thus providing a counterflow of.

bustion unit in said combustion chamber, flue gas conduits provided in said combustion chamber; other flue gas conduits provided in said heat exchange chamber; a condensate trap connected with the lower. end portions of the conduits in said heat exchange chamber and forming a flue gas manifold; short pipes communicating with and extending outwardly from said manifold;

'and readily releasable telescopic sleeve means adapted to connect said short pipes with the conduits' from said combustion chamber.

3. In a'furnace, means forming two air circulation' chamibers positioned side by sidefor the intake and discharge of air to be heated; air intake and discharge means connected with the upper end portions of the respective chambers;

' fan means positioned to draw air downwardly throughsaid air intake chamberand force the same upwardly through said air discharge chamber; a combustion chamber of smaller cross sectional dimensions than said air discharge chamber extending substantially from bottom to top of said air discharge chamber; substantially horizontal-smoke pipes extending around'the comlbuStiOn chamber at a substantial distance below I the top thereof; upright smoke pipes connecting the upper end portion of saidcombustion chambar with said substantially horizontal smoke a a temperature below 100 F. In the ordinary gas.

pipes; a plurality of spaced apart balile plates in the air intake chamber alternately terminating in spaced relation from opposite walls thereof;

a plurality. of smoke pipes extending back and forth in the air circulation spaces between said I bafiles; a condensate trap having an upper manifold cap portion connected with the lower end portions of said last mentioned smoke pipes and with said substantially horizontal smoke pipes;

all of said pipes having a downward incline to filter extending across said air intake chamber deliver to said condensate trap; flue means connected with the upper end portions of the smoke pipes in said air intake chamber; and an. air

- above said fan means. I

4. In a furnace, means forming two air circulation chambers positioned side by side for the intake and discharge of air to be heatediair intake and discharge means connected with the upper end portions of the respective chambers;

fan means positioned to draw air. downwardly through said,v air intake chamber and' forcethe same upwardly through said air discharge chamber; a combustion chamber of smaller cross sectional dimensions than said air discharge chamber extending, substantially from bottom to top of said'air discharge chamber; substantially horizontal smoke pipe means extending around the combustion chamber at a substantial distance below the top thereof; a plurality ofupfurnace housing communicatingwith' said combustion chamber and extending into said heat exchange chamber and communicating with said cap member; and other flue gas conduits in said heat exchange chamber communicating with said right smoke pipesconne'cted with the upper end portion of said combustion chamber and with said substantially horizontal smoke pipe'means v and extending longitu'dinallywithin saidair discap member, said cap member constituting a w manifold for the passage of flue. gas from one set of conduits to the other. I

2. In a furnace, means forming a combustion chamber and a heat'exchange chamber; a com-.

charge chamberjcondensate removalmeans connected with said substantially horizontal smoke pipe means; a plurality of smoke pipes in said air intake chamber communicating with said subvstantially horizontal smoke pipe means; and flue means connected with the upper end portio-m of the smoke pipes in said air intake chamber.

' JOHN A. NORTON. 

